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The autotrophic acetogen Clostridium ljungdahlii has emerged as a major candidate in the biological conversion of one-carbon gases (CO2/CO) to bulk chemicals and fuels. Nevertheless, the regulatory pathways and downstream metabolic changes responsible for product formation and distribution in this bacterium remain minimally explored. Protein lysine acetylation (PLA), a prevalent posttranslational modification, controls numerous crucial cellular functions. Herein, we revealed a novel cross-regulatory mechanism that uses both the PLA system and transcription factors to regulate the carbon flow distribution for product formation in C. ljungdahlii. The dominant acetylation/deacetylation system (At2/Dat1) in C. ljungdahlii was found to regulate the ratio of two major products, acetic acid and ethanol. Subsequent genetic and biochemical analyses revealed that the activities of Pta and AdhE1, two crucial enzymes responsible for acetic acid and ethanol synthesis, respectively, were greatly affected by their levels of PLA. We found that the acetylation statuses of Pta and AdhE1 underwent significant dynamic changes during the fermentation process, leading to differential synthesis of acetic acid and ethanol. Furthermore, the crucial redox-sensing protein Rex was shown to be regulated by PLA, which subsequently altered its transcriptional regulation on genes responsible for acetic acid and ethanol formation and distribution. Based on our understanding of this cross-regulatory module, we optimized the ethanol synthetic pathway by modifying the acetylation status (deacetylation-mimicked mutations of crucial lysine residues) of the related key enzyme, achieving significantly increased titer and yield of ethanol, an important chemical and fuel, by C. ljungdahlii in gas fermentation. [ABSTRACT FROM AUTHOR]

Chiral α-alkyl α-glycine acids are prevalent structural motifs found in pharmaceuticals and natural products, making them a significant dimension for exploration in modern pharmaceutical and medicinal chemistry. However, the current synthesis methods for these compounds face numerous environmental and practical challenges, highlighting the critical need to establish more sustainable approaches. Herein, we report the first liquid assisted grinding (LAG)-facilitated aerobic asymmetric cross-dehydrogenative coupling reaction involving glycine esters/amides and simple ketones/aldehydes, using a chiral amine catalyst under metal-free and solvent-minimal conditions. A wide variety of α-alkyl α-amino acid derivatives, containing two or three stereocenters, were generated in good yields with remarkable enantioselectivity and diastereoselectivity. Moreover, we propose a new enantioselective control model for mechanical ball milling, suggesting that stoichiometric EtOH may enhance the enantioselectivity by potentially interacting with both the catalyst and the imine ion intermediate. This method, closely aligned with the principles of green chemistry, offers a recoverable catalyst/grinding-aid system, has broad substrate compatibility, and enables the synthesis of multifunctionalized products suitable for diverse transformations, notably including the production of the unnatural amino acid L-cyclohexylglycine (a key intermediate in telaprevir synthesis). [ABSTRACT FROM AUTHOR]

In order to accurately separate the elastic and inelastic deformation information caused by aquifer compression in the land subsidence signal, and to invert the hydrogeological parameters of high spatial and temporal resolution to better apply the groundwater-ground subsidence model, a CWT (Continuous Wavelet Transform) separation method for aquifer elastic and inelastic deformation signals based on CWT is adopted, and the deformation signal is extracted by InSAR technology. The large-scale synthetic aperture radar dataset obtained by Envisat satellite from 2007 to 2009 is collected to obtain the surface deformation characteristic of the area by SBAS-InSAR technology, and then the independence provided by the observation well is used. Using the independent water level data provided by the observation wells, combined with the vertical InSAR deformation component and the head data, the CWT method is used to separate the periodic deformation signal components and long-term trends. Finally, the isolated signal component is used to invert the elastic and inelastic storage coefficient based on the ground subsidence model. The settlement signal separation method used in this paper makes up for the shortcomings of the two kinds of information in the previous settlement signal that are difficult to separate, which allows for more accurate inversion of aquifer parameters and helps to understand the aquifer parameters and continuously manage groundwater resources. [ABSTRACT FROM AUTHOR]

Background: Hyaluronan synthases (HAS) control the biosynthesis of hyaluronan (HA) and critically modulate the tumor microenviroment. Cancer associated fibroblasts (CAFs) affect the progression of a tumor by remolding the matrix. However, little is known about the role of HAS from CAFs in this process. This study aimed to determine the role of hyaluronan synthase 2 (HAS2) from CAFs in the progression of oral squamous cell carcinoma (OSCC) invasion. Methods: HAS isoforms 1, 2, and 3 in paired sets of CAFs and normal fibroblasts (NFs) were examined by real-time PCR, and the expression of HAS2 and ɑ-SMA in OSCC tissue sections was further evaluated using immunohistochemical staining. Furthermore, we used a conditioned culture medium model to evaluate the effects of HAS2 from CAFs on the invasion and epithelial-mesenchymal transition (EMT) of the oral cancer cells Cal27. Finally, we compared the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) between CAFs and NF, and between CAFs with or without HAS2 knockdown using an antibody array and western blotting. Results: CAFs expressed higher levels of HAS2 than the paired NFs. HAS2 expression was consistent with ɑ SMA positive myofibroblasts in the stroma of OSCC, and these were significantly correlated advanced clinical stages and cervical lymph node metastasis. Knocking down HAS2 with a specific siRNA or treatment with a HAS inhibitor markedly attenuated CAF induced invasion and EMT of Cal27 cells. Higher MMP1 and lower TIMP1 levels were detected in the supernatants of CAFs relative to NFs. Knocking down HAS2 could decrease the expression of MMP1 and increase that of TIMP1 in CAFs. Conclusions: HAS2 is one of the key regulators responsible for CAF mediated OSCC progression and acts by modulating the balance of MMP1 and TIMP1 [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Ethanol-assisted mechanochemical asymmetric cross-dehydrogenative coupling reaction with recoverable chiral amine/NaCl for accessing chiral α-alkyl α-glycine derivatives" published in the journal Green Chemistry. The authors acknowledge inaccuracies in the mechanism and associated discussion in the original article. They provide a corrected scheme and clarify a sentence within the main article. The Royal Society of Chemistry apologizes for the errors. The document also includes information about the authors' affiliations and contact details. [Extracted from the article]

Objective: To investigate the effects of Xingnao Kaiqiao acupuncture in the treatment of lower limb dysfunction after stroke. Methods: A total of 100 cases of patients with lower limb dysfunction after stroke in our hospital were selected and divided into the control group and the observation group, 50 cases in each group by the random number table method. The control group was treated with conventional transcranial magnetic stimulation while the observation group was additionally treated with Xingnao Kaiqiao acupuncture. The 10-meter walk test (10 mWT) and the timed up and go test time (TUGT) were performed in the two groups before and after the intervention. The walking function, lower limb motor function, neurological function and activities of daily living were evaluated with the Fugl-Meyer Assessment (FMA) of motor function, the Holdden walking function rating scale (FAC), the modified Fugl-Meyer motor function rating scale (FMA), the National Institutes of Health Stroke Scale (NIHSS) and Barthel index (BI) in activity of daily living scale (ADL), and changes of lower limb muscle tension were determined by the Ashworth scale. Results: 1 After the intervention, the 10 mWT was increased and TUGT was shortened in the two groups (P < 0.05). The 10 mWT of the observation group was longer than that of the control group, while TUGT was shorter than that of the control group (P < 0.05). 2 Before the intervention, there were no significant differences between the two groups in scores of FAC and FMA (P > 0.05). After the intervention, scores in the two groups were increased (P < 0.05), and the scores of observation group were higher than those of the control group (P < 0.05). 3 The proportion of grade 0 lower limb muscle tension in the observation group after 10 weeks of intervention was higher than that in the control group (P < 0.05). 4 After the intervention, NIHSS scores were decreased and BI scores were increased in the two groups (P < 0.05). The NIHSS score of the observation group was lower than that of the control group, and the BI score was higher than that of the control group (P < 0.05). Conclusion: Xingnao Kaiqiao acupuncture combined with transcranial magnetic stimulation can reduce the degree of lower limb dysfunction, promote the improvement of walking function and improve the lower limb muscle strength and activities of daily living of patients after stroke. [ABSTRACT FROM AUTHOR]

Persistent scatterers synthetic aperture radar interferometry (PSInSAR) technology has been applied in the context of deformation monitoring of transportation infrastructures such as bridges, highways, and railways. However, extracting and interpreting information from long-time series displacement obtained using PS-InSAR is a complex and demanding task. In this study, time series analysis was used to post-process the displacement time series derived from PSInSAR using 100 stripmap mode images collected by TerraSAR-X satellite during 13 April 2010 and 13 December 2019. Seasonal and trend decomposition using loess (STL) and variational modal decomposition (VMD) were combined to estimate the different periodic and trend components of the total displacement time series. Temperature correlation was then generated by associating the different period components with the temperature change. The results show that the deformation of Sihui overpass, Sifang overpass and Shibalidian overpass in Beijing Fourth Ring Road highway is obvious. The trend components obtained by STL decomposition of the selected typical points are primarily nonlinear deformation, and the deformation of Sifang overpass, Shibalidian overpass and Liuxiang overpass slows to varying degrees. After decomposing the displacement time series into several intrinsic mode functions (imf) with finite bandwidth using VMD, the thermal expansion phenomenon is pronounced on the main bridge and approach bridge of some overpasses. Seasonal imf1 is an annual periodic that appears to be highly positively correlated with temperature change. Seasonal imf2 is a period term of greater than one year that confirms that the bridges exhibit other periodic seasonal components in addition to the seasonal deformation of annual period. The thermal expansion characteristics of different periodic seasonal components that are explored in this study can provide valuable information for better understanding the thermal expansion evolution process, and these findings are important scientific significance for bridge structure health monitoring. [ABSTRACT FROM AUTHOR]

The surface deformation monitoring in coastal areas is affected by the uncertainty of flow control, which leads to the low accuracy of surface deformation monitoring. In order to improve the accuracy of surface deformation monitoring in coastal areas, an automatic monitoring method of surface deforma tion in coastal areas based on time series analysis is proposed. The big data structure model of surface deformation in coastal areas is constructed, and the distributed information reconstruction of surface deformation in coastal areas is carried out by using phase space reconstruction and correlation coefficient mining methods. Big data fusion cluster analysis of surface deformation in coastal areas is carried out combined with time series analysis method. The dynamic distribution characteristics of surface deformation big data in coastal areas are extracted, and the clustering and information fusion results of surface deformation characteristics in coastal areas are obtained. The automatic monitoring of surface deformation dynamics in coastal areas is realized. The simulation results show that the accuracy of automatic monitoring of surface deformation in coastal areas is high, and the average confidence level of monitoring is better than that of traditional methods, which improves the adaptability of surface deformation monitoring in coastal areas. [ABSTRACT FROM AUTHOR]